Addicalco Adding Machine

This full-keyboard key-driven non-printing adding machine has a gray case. White and green plastic keys have complementary digits indicated on each key. Keys representing even digits are flat, and those representing odd numbers are indented. In front of these keys is a horizontal row of keys numbered from 8 to 1 going left to right. In front of these is a row of eight levers used as decimal markers for the result, which appears in a row of nine windows at the very front. The zeroing lever is right of the keyboard. In back of it is a red key.
The machine is marked on the top: Addicalco. It is marked on the front: H A*C*C*A MILANO (/) MADE IN ITALY. It is marked at the back of the keyboard with serial number: 49-003725. This is model #306 from the Patent Division of Burroughs Corporation.
The firm ACCA was founded in Milan after World War II and began manufacturing an adding machine called the Addicalco on the pattern of the model J Comptometer. This is a somewhat later version of the Addicalco, the model 49, from about 1949.
Compare MA*323644, MA*309393 and MA*328128.
Currently not on view
Object Name
adding machine
date made
A. C. C. A.
Physical Description
steel (overall material)
rubber (overall material)
plastic (overall material)
overall: 15 cm x 25 cm x 38 cm; 5 29/32 in x 9 27/32 in x 14 31/32 in
place made
Italia: Lombardia, Milan
ID Number
accession number
catalog number
Science & Mathematics
Adding Machines
See more items in
Medicine and Science: Mathematics
Adding Machines
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Gift of Burroughs Corporation
Additional Media

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